The officers may have to take as many as 14 days of unpaid time off, or furloughs, and see their typical work hours cut to 8 from 10 as overtime is scaled back by U.S. Customs and Border Protection, said Shawn Moran, vice president of the National Border Patrol Council, representing 17,000 non-supervisory agents.

“The smuggling organizations are keenly aware of what our operational capabilities are,” said Moran, who’s based in San Diego. “Once they see that we don’t have the manpower we had out on the border previously, they will take advantage.”

Across-the-board budget cuts known as sequestration are forcing government agencies to reduce spending. The government must trim $85 billion for the rest of this fiscal year, which ends Sept. 30, distributed evenly between defense and non- defense portions of the budget.

Customs and Border Protection funding is expected to be reduced by more than $500 million, according to a March 1 report by the White House Office of Management and Budget. Homeland Security Secretary Janet Napolitano, whose department includes the Border Patrol, told Congress last month the department will have to shrink hours equivalent to the salaries of 5,000 Border Patrol agents and 2,750 Customs and Border Protection officers beginning April 1.

The Customs and Border Protection agency is trying to reduce its budget in a way that is “least disruptive to the facilitation of lawful travel and trade and our employees, while not compromising our security mission,” said Jenny Burke, a Washington-based spokeswoman.

“Because CBP is reducing, but not absolutely eliminating overtime pay, and because the length of the sequestration is unknown, it is difficult to project the impact of the reductions,” Burke said by e-mail.

The cuts follow the release last week of hundreds of immigrant detainees by U.S. Immigration and Customs Enforcement, attributed to sequestration. Arizona Governor Jan Brewer, a critic of President Obama’s administration on border issues, said the releases were “payback” to her state for its attempts to curb illegal immigration, such as the 2010 crackdown she signed.

The governor’s spokesman, Matthew Benson, said the Border Patrol reductions would be “outrageous” and could put Arizonans at risk.

“The White House approach to sequestration seems to be to create as much pain and public panic as possible,” Benson said in a telephone interview. “Any cut that impacts public safety should be a last resort.”

Joe Arpaio, elected to his sixth term as sheriff of Maricopa County, Arizona’s largest, as he faced a federal civil- rights lawsuit over immigration-related arrests, criticized the planned reduction.

“You shouldn’t take away resources when you still have a problem,” Arpaio, 80, said Tuesday in an interview. “It doesn’t make sense.”

The furloughs and loss of overtime are equivalent to a 35 percent pay cut for Border Patrol agents, David Cox, national president of the American Federation of Government Employees, said in a statement. The group is the parent union of the border patrol council.

“Agents will be instructed to stop working at the moment their straight shift ends,” Cox said. “Good news for criminals and others who would enter our country illegally; but very bad news for Americans who rely on the courage and devotion of Border Patrol agents who risk their lives every day to keep drugs and guns and gangs outside our borders.”

The cuts probably won’t dramatically increase crime or significantly compromise border security, said Chris Wilson, an associate with the Wilson Center’s Mexico Institute, a Washington-based research group. The number of Border Patrol agents has doubled in the last decade, and illegal activity along the border between the ports of entry has fallen.

Border Patrol is “bigger than they’ve ever been and crossings are lower than they’ve ever been,” Wilson said in a telephone interview. The proposed cuts “would not put us at staffing levels unlike what we had in recent years and, therefore, would not put us at a point that we would have major security concerns as a result.”